The present invention relates generally to vacuum cleaners, and more specifically to a V-belt driven vacuum cleaner brushroll.
One typical vacuum cleaner brushroll has a wood spindle or dowel that is provided with a pulley for coacting with a V-belt having grooves or slots extending lengthwise on the belt in its inner surface. Conventionally, both the power shaft pulley and the brushroll pulley have teeth that coact with the grooves of the V-belt.
In the conventional construction described above, the brushroll pulley is an injection molded member which is pressed fitted over the end of the dowel. In order to form a positive lock between the pulley and the spindle, holes have been drilled in the pulley collar and some of the brushroll bristles have been inserted through the holes into the dowel. Heretofore, the provision of a toothed pulley on the dowel has been considered necessary when using a V-belt as previously described.
The present invention is based on the discovery that it is not necessary to provide a toothed brushroll pulley in a V-belt type drive system in which the V-belt has grooves in its inner surface extending lengthwise of the belt.
In accordance with this invention, a vacuum brushroll has a pulley characterized by smooth, flat V-belt engaging surface that is parallel to the brushroll axis. The smooth V-belt engaging surface surprisingly obtains substantially the same torque as a pulley formed with ribs that interact with the grooves of the V-belt. Since it is not necessary to have a ribbed pulley in order to achieve the desired torque, the pulley and spindle can be formed as one piece. In the case of a wood dowel, the smooth pulley is simply machined in the outer surface of the dowel. By eliminating the need for a separately formed ribbed pulley, the invention materially decreases the cost of manufacturing brushrolls driven by a grooved V-belt.
Many other advantages and a fuller understanding of the invention will be had from the following detailed description and the accompanying drawings.